Pioneer CDS-P5000 UC, Service Manual

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CDS-P5000
7.2.2 TEST MODE
1)Precautions
• This unit uses a single power supply (+5V) for the
regulator. The signal reference potential, therefore, is
connected to REFO(approx. 2.5V) instead of GND.
If REFO and GND are connected to each other by mis-
take during adjustments,not only will it be impossible
to measure the potential correctly,but the servo will
malfunction and a severe shock will be applied to the
pick-up. To avoid this,take special note of the follow-
ing.
Do not connect the negative probe of the measuring
equipment to REFO and GND together. It is especially
important not to connect the channel 1 negative
probe of the oscilloscope to REFO with the channel 2
negative probe connected to GND.
Since the frame of the measuring instrument is usual-
ly at the same potential as the negative probe,change
the frame of the measuring instrument to floating sta-
tus.
If by accident REFO comes in contact with
GND,immediately switch the regulator or power OFF.
• Always make sure the regulator is OFF when connect-
ing and disconnecting the various filters and wiring
required for measurements.
• Before proceeding to further adjustments and mea-
surements after switching regulator ON,let the player
run for about one minute to allow the circuits to sta-
bilize.
• Since the protective systems in the unit’s software are
rendered inoperative in test mode,be very careful to
avoid mechanical and /or electrical shocks to the sys-
tem when making adjustment.
• This unit is adjusted in a combination with the CD
control unit (KEH-P7000, etc.). Each regulator key
should be operated at the unit.
With the KEH-P7000 taken up for reference, a descrip-
tion will be given below concerning how to enter into
the test mode, including key operations. The key in
the adjustment text is also one of the KEH-P7000
keys.
• How to enter into the test mode
Switch ACC,back-up ON while pressing the 4 and 6
keys together.
• Resetting the test mode
Switch ACC,back-up Off.
• Disc detection during loading and eject operations is
performed by means of a photo transistor in this
unit.Consequently,if the inside of the unit is exposed
to a strong light source when the outer casing is
removed for repairs or adjustment,the following mal-
functions may occur.
*During PLAY, even if the eject button is pressed,the
disc will not be ejected and the unit will remain in
the PLAY mode.
*The unit will not load a disc.
When the unit malfunctions this way,either re-posi-
tion the light source,move the unit or cover the
photo transistor.
• When loading and unloading discs during adjustment
procedures,always wait for the disc to be properly
clamped or ejected before pressing another key.
Otherwise, there is a risk of the actuator being
destroyed.
• Turn power off when pressing the button FF or the
button REV key for focus search in the test mode. (Or
else lens may stick and the actuator may be dam-
aged.)
• SINGLE/4TRK/10TRK/32TRK will continue to operate
even after the key is released.Tracking is closed the
moment C-MOVE is released.
• JUMP MODE resets to SINGLE as soon as power is
switched off.